/* Copyright (C) 2000 MySQL AB

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */

/* Parser needs these defines  always, even if USE_RAID is not defined */
#define RAID_TYPE_0 1 /* Striping */
#define RAID_TYPE_x 2 /* Some new modes */
#define RAID_TYPE_y 3

#define RAID_DEFAULT_CHUNKS 4
#define RAID_DEFAULT_CHUNKSIZE 256 * 1024 /* 256kB */

C_MODE_START
#define my_raid_type(raid_type) raid_type_string[(int)(raid_type)]
extern const char *raid_type_string[];
C_MODE_END

#ifdef DONT_USE_RAID
#undef USE_RAID
#endif
#if defined(USE_RAID)

#include "my_dir.h"

/* Trap all occurences of my_...() in source and use our wrapper around this function */

#ifdef MAP_TO_USE_RAID
#define my_read(A, B, C, D) my_raid_read(A, B, C, D)
#define my_write(A, B, C, D) my_raid_write(A, B, C, D)
#define my_pwrite(A, B, C, D, E) my_raid_pwrite(A, B, C, D, E)
#define my_pread(A, B, C, D, E) my_raid_pread(A, B, C, D, E)
#define my_chsize(A, B, C, D) my_raid_chsize(A, B, C, D)
#define my_close(A, B) my_raid_close(A, B)
#define my_tell(A, B) my_raid_tell(A, B)
#define my_seek(A, B, C, D) my_raid_seek(A, B, C, D)
#define my_lock(A, B, C, D, E) my_raid_lock(A, B, C, D, E)
#define my_fstat(A, B, C) my_raid_fstat(A, B, C)
#endif /* MAP_TO_USE_RAID */

#ifdef __cplusplus
extern "C"
{
#endif

  void init_raid(void);
  void end_raid(void);

  bool is_raid(File fd);
  File my_raid_create(const char *FileName, int CreateFlags, int access_flags, uint raid_type, uint raid_chunks,
                      ulong raid_chunksize, myf MyFlags);
  File my_raid_open(const char *FileName, int Flags, uint raid_type, uint raid_chunks, ulong raid_chunksize,
                    myf MyFlags);
  int my_raid_rename(const char *from, const char *to, uint raid_chunks, myf MyFlags);
  int my_raid_delete(const char *from, uint raid_chunks, myf MyFlags);
  int my_raid_redel(const char *old_name, const char *new_name, uint raid_chunks, myf MyFlags);

  my_off_t my_raid_seek(File fd, my_off_t pos, int whence, myf MyFlags);
  my_off_t my_raid_tell(File fd, myf MyFlags);

  uint my_raid_write(File, const byte *Buffer, uint Count, myf MyFlags);
  uint my_raid_read(File Filedes, byte *Buffer, uint Count, myf MyFlags);

  uint my_raid_pread(File Filedes, byte *Buffer, uint Count, my_off_t offset, myf MyFlags);
  uint my_raid_pwrite(int Filedes, const byte *Buffer, uint Count, my_off_t offset, myf MyFlags);

  int my_raid_lock(File, int locktype, my_off_t start, my_off_t length, myf MyFlags);
  int my_raid_chsize(File fd, my_off_t newlength, int filler, myf MyFlags);
  int my_raid_close(File, myf MyFlags);
  int my_raid_fstat(int Filedes, struct stat *buf, myf MyFlags);

#ifdef __cplusplus
}

#ifdef USE_PRAGMA_INTERFACE
#pragma interface /* gcc class implementation */
#endif

class RaidName
{
 public:
  RaidName(const char *FileName);
  ~RaidName();
  bool IsRaid();
  int Rename(const char *from, const char *to, myf MyFlags);

 private:
  uint _raid_type;       /* RAID_TYPE_0 or RAID_TYPE_1 or RAID_TYPE_5 */
  uint _raid_chunks;     /* 1..n */
  ulong _raid_chunksize; /* 1..n in bytes */
};

class RaidFd
{
 public:
  RaidFd(uint raid_type, uint raid_chunks, ulong raid_chunksize);
  ~RaidFd();
  File Create(const char *FileName, int CreateFlags, int access_flags, myf MyFlags);
  File Open(const char *FileName, int Flags, myf MyFlags);
  my_off_t Seek(my_off_t pos, int whence, myf MyFlags);
  my_off_t Tell(myf MyFlags);
  int Write(const byte *Buffer, uint Count, myf MyFlags);
  int Read(const byte *Buffer, uint Count, myf MyFlags);
  int Lock(int locktype, my_off_t start, my_off_t length, myf MyFlags);
  int Chsize(File fd, my_off_t newlength, int filler, myf MyFlags);
  int Fstat(int fd, MY_STAT *stat_area, myf MyFlags);
  int Close(myf MyFlags);
  static bool IsRaid(File fd);
  static DYNAMIC_ARRAY _raid_map; /* Map of RaidFD* */
 private:
  uint _raid_type;       /* RAID_TYPE_0 or RAID_TYPE_1 or RAID_TYPE_5 */
  uint _raid_chunks;     /* 1..n */
  ulong _raid_chunksize; /* 1..n in bytes */

  ulong _total_block;    /* We are operating with block no x (can be 0..many). */
  uint _this_block;      /* can be 0.._raid_chunks */
  uint _remaining_bytes; /* Maximum bytes that can be written in this block */

  my_off_t _position;
  my_off_t _size; /* Cached file size for faster seek(SEEK_END) */
  File _fd;
  File *_fd_vector;    /* Array of File */
  off_t *_seek_vector; /* Array of cached seek positions */

  inline void Calculate()
  {
    DBUG_ENTER("RaidFd::_Calculate");
    DBUG_PRINT("info",
               ("_position: %lu _raid_chunksize: %d, _size: %lu", (ulong)_position, _raid_chunksize, (ulong)_size));

    _total_block = (ulong)(_position / _raid_chunksize);
    _this_block = _total_block % _raid_chunks; /* can be 0.._raid_chunks */
    _remaining_bytes = (uint)(_raid_chunksize - (_position - _total_block * _raid_chunksize));
    DBUG_PRINT("info",
               ("_total_block: %d  this_block: %d  _remaining_bytes:%d", _total_block, _this_block, _remaining_bytes));
    DBUG_VOID_RETURN;
  }
};

#endif /* __cplusplus */
#endif /* USE_RAID */
